Mapping hot CO in DR21-C
Abstract
We plan to spatially resolve the physical and dynamical structure of the massive star forming region DR21-C which has a prominent bipolar outflow visible in 2 micron emission of vibrationally excited H2, tracing hot, shocked gas. Particularly, we want to measure the local variation of the shock contribution to the CO excitation. While the shock is hardly affecting most of the molecular line emission of the region, only CII shows an additional broad wing indicating that the CII emission is not only originating from the warm gas, but also from the ionized wind in the blister outflow. Recent Herschel/HIFI observations of hot CO emission lines along and across the outflow direction reveal a more complex dynamical structure of the highly excited gas. The gas dynamics and energetics change significantly toward energetically higher lying states and hint at multiple, differently excited gas components. We propose to map the area around the central cluster in the 12CO J=11-10, J=13-12, and J=16-15 lines to spatially resolve the highly excited molecular material in DR21. Since the three different lines are subject to different excitation conditions the proposed maps will allow us to spatially resolve the local gas energetics at different beam sizes (16, 20, and 23 arcsec). These will be the first spatially and spectrally resolved maps of very high-J CO emission of a Galactic PDR and will greatly help to increase ouor understanding of the interplay between PDR and shock excitation in massive star forming regions.
- Publication:
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SOFIA Proposal
- Pub Date:
- October 2013
- Bibcode:
- 2013sofi.prop...49R
- Keywords:
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- SOFIA 02_0049